This paper proposes a unified efficient and universal scalable video coding framework that supports different scalabilities, such as fine granularity quality, temporal, spatial and complexity scalabilities. The proposed framework is established upon the recent studies in fine granularity scalable (FGS) video coding. It contains two key points. Firstly, in order to improve the coding efficiency of the proposed framework, more than one motion compensation loop is used. Since high quality references are introduced into the enhancement layer coding, the proposed framework can efficiently compress different-resolution video at different layers for the purpose of the complexity and spatial scalability. Secondly, the drifting reduction techniques are studied in this paper. This helps the proposed framework to maintain good performance at lower enhancement bit rates. By defining coding modes, a macroblock level control mechanism is developed to achieve a better trade-off between low drifting ...